Egeria densa Allelopathy on Microcystis aeruginosa Under Different Light Intensities and Preliminary Insight into Inter-Parameter Relationships

Light is an important factor that affects cyanobacterial growth and changes in light can influence their growth and physiology. However, an information gap exists regarding light-induced oxidative stress and the species-specific behavior of cyanobacteria under various light levels. This study was conducted to evaluate the comparative effects of different light intensities on the growth and stress responses of two cyanobacteria species, Pseudanabaena galeata (strain NIES 512) and Microcystis aeruginosa (strain NIES 111), after periods of two and eight days. The cyanobacterial cultures were grown under the following different light intensities: 0, 10, 30, 50, 100, 300, and 600 μmol m−2 s−1. The optical density (OD730), chlorophyll a (Chl-a) content, protein content, H2O2 content, and the antioxidative enzyme activities of catalase (CAT) and peroxidase (POD) were measured separately in each cyanobacteria species. P. galeata was negatively affected by light intensities lower than 30 μmol m−2 s−1 and higher than 50 μmol m−2 s−1. A range of 30 to 50 μmol m−2 s−1 light was favorable for the growth of P. galeata, whereas M. aeruginosa had a higher tolerance for extreme light conditions. The favorable range for M. aeruginosa was 10 to 100 μmol m−2 s−1.

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New insight into the residual inactivation of Microcystis aeruginosa by dielectric barrier discharge

Scientific Reports ◽

10.1038/srep13683 ◽

2015 ◽

Vol 5 (1) ◽

Cited By ~ 10

Author(s):

Lamei Li ◽

Hong Zhang ◽

Qing Huang

Keyword(s):

Dielectric Barrier Discharge ◽

Microcystis Aeruginosa ◽

Barrier Discharge ◽

Dielectric Barrier ◽

Insight Into

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Genome analysis and gene nblA identification of Microcystis aeruginosa myovirus (MaMV-DC) reveal the evidence for horizontal gene transfer events between cyanomyovirus and host

Journal of General Virology ◽

10.1099/jgv.0.000290 ◽

2015 ◽

Vol 96 (12) ◽

pp. 3681-3697 ◽

Cited By ~ 19

Author(s):

Tong Ou ◽

Xiao-Chan Gao ◽

San-Hua Li ◽

Qi-Ya Zhang

Keyword(s):

Gene Transfer ◽

Horizontal Gene Transfer ◽

Microcystis Aeruginosa ◽

Trna Gene ◽

Genetic Characterization ◽

Significant Decline ◽

Lake Dianchi ◽

Protein Coding ◽

Efficient Expression ◽

Insight Into

The genome sequence, genetic characterization and nblA gene function of Microcystis aeruginosa myovirus isolated from Lake Dianchi in China (MaMV-DC) have been analysed. The genome DNA is 169 223 bp long, with 170 predicted protein-coding genes (001L–170L) and a tRNA gene. About one-sixth of these genes have homologues in the host cyanobacteria M. aeruginosa. The genome carries a gene homologous to host nblA, which encodes a protein involved in the degradation of cyanobacterial phycobilisome. Its expression during MaMV-DC infection was confirmed by reverse transcriptase PCR and Western blot detection and abundant expression was companied by the significant decline of phycocyanin content and massive release of progeny MaMV-DC. In addition, expressing MaMV-DC nblA reduced the phycocyanin peak and the phycocyanin to chlorophyll ratio in model cyanobacteria. These results confirm that horizontal gene transfer events have occurred between cyanobacterial host and cyanomyovirus and suggest that MaMV-DC carrying host-derived genes (such as 005L, that codes for NblA) is responsible for more efficient expression of cyanophage genes and release of progeny cyanophage. This study provides novel insight into the horizontal gene transfer in cyanophage and the interactions between cyanophage and their host.

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Calibration problems in hydrogen luminosities

Symposium - International Astronomical Union ◽

10.1017/s0074180900053626 ◽

1966 ◽

Vol 24 ◽

pp. 322-330

Author(s):

A. Beer

Keyword(s):

Galactic Structure ◽

B Stars ◽

Insight Into

The investigations which I should like to summarize in this paper concern recent photo-electric luminosity determinations of O and B stars. Their final aim has been the derivation of new stellar distances, and some insight into certain patterns of galactic structure.

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Stochasting modeling of planetary ring systems

International Astronomical Union Colloquium ◽

10.1017/s025292110010154x ◽

1984 ◽

Vol 75 ◽

pp. 461-469 ◽

Cited By ~ 1

Author(s):

Robert W. Hart

Keyword(s):

Maximum Entropy ◽

Ring System ◽

The Sun ◽

Ultimate State ◽

Interparticle Interactions ◽

Ring Systems ◽

First Order ◽

Planetary Ring ◽

Insight Into

ABSTRACTThis paper models maximum entropy configurations of idealized gravitational ring systems. Such configurations are of interest because systems generally evolve toward an ultimate state of maximum randomness. For simplicity, attention is confined to ultimate states for which interparticle interactions are no longer of first order importance. The planets, in their orbits about the sun, are one example of such a ring system. The extent to which the present approximation yields insight into ring systems such as Saturn's is explored briefly.

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Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074768 ◽

1983 ◽

Vol 41 ◽

pp. 194-195

Author(s):

D. F. Blake ◽

L. F. Allard ◽

D. R. Peacor

Keyword(s):

High Resolution ◽

Marine Invertebrates ◽

Sea Urchins ◽

Structural Features ◽

Sea Stars ◽

High Resolution Tem ◽

Relationship Of ◽

The Relationship ◽

Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

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Structure and function of neural networks in the retina

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102213 ◽

1988 ◽

Vol 46 ◽

pp. 26-27

Author(s):

Peter Sterling

Keyword(s):

Ganglion Cells ◽

Three Dimensional ◽

Structure And Function ◽

Synaptic Connections ◽

Visual Axis ◽

One Dimensional ◽

Cat Retina ◽

Ultrathin Sections ◽

And Function ◽

Insight Into

The synaptic connections in cat retina that link photoreceptors to ganglion cells have been analyzed quantitatively. Our approach has been to prepare serial, ultrathin sections and photograph en montage at low magnification (˜2000X) in the electron microscope. Six series, 100-300 sections long, have been prepared over the last decade. They derive from different cats but always from the same region of retina, about one degree from the center of the visual axis. The material has been analyzed by reconstructing adjacent neurons in each array and then identifying systematically the synaptic connections between arrays. Most reconstructions were done manually by tracing the outlines of processes in successive sections onto acetate sheets aligned on a cartoonist's jig. The tracings were then digitized, stacked by computer, and printed with the hidden lines removed. The results have provided rather than the usual one-dimensional account of pathways, a three-dimensional account of circuits. From this has emerged insight into the functional architecture.

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